From U.S. Pat. No. 5,372,196 is previously known a percussion device of this kind. This percussion device includes a percussion piston, which is reciprocatingly movable inside a machine housing. The reciprocating movement of the percussion piston is controlled by a valve device, wherein the valve element is movable to and fro in the machine housing. At its rear end, the machine housing has a space which is supplied with pressure fluid and thus drives the percussion piston in the forward direction. A second chamber that can be pressurized is arranged for back-driving the percussion piston.
The known percussion device functions well and aims to obtain percussive frequencies in the magnitude of 150 Hz. Recently raised desires of higher work rate and better economy in rock drilling have, however, resulted in the desire for yet higher percussive frequencies.